How to Build Exhaust Textures?

[Zatnikitelman]

I've looked around at both the exhaust textures included with Orbiter and done some searching for a guide or something, but I still can't figure out exactly how/why an exhaust texture has to be the way it is.
Does anyone have any info on building these textures?
Thanks,
Zat

 

[ar81]

I understand you need to use one image for texture and another for alpha channel (transparency). I just do not remember how you combine them together for a DDS.

 

[Zatnikitelman]

Ok, I know you need an alpha channel of some sort, but how do you generate it? I have GIMP and its DDS plugin so it should be easier to import/export stuff and I'm looking at the exhaust textures I have otherwise installed, but I just can't figure out what each section is for.

 

[ar81]

Texture bug report ... http://orbiter-forum.com/project.php?issueid=7

How to create DDS textures
http://www.rnbcreative.at/cms/uploads/media/mp2_03e_Creating_DDS_Textures.pdf
http://www.xtremevbtalk.com/showthread.php?t=68328

I used Google to look for DDS alpha channel.
A deeper search could probably get you more results.

 

[no matter]

Ok, I know you need an alpha channel of some sort, but how do you generate it? I have GIMP and its DDS plugin so it should be easier to import/export stuff and I'm looking at the exhaust textures I have otherwise installed, but I just can't figure out what each section is for.

It is not hard but unfortunately I don't use the Gimp so i am affraid I can't really help.
You just need to save the .dds using DXT5 format (that should be selectable via the plugin inside gimp).

For the alpha channel, let's say you have usually 3 channels (RGB) and now you want one more channel, the alpha channel which tells orbiter what is transparent and what is not in your exhaust texture.
You have to create that channel with gimp, using black white or grey. Unfortunately, I don't know how do that with the Gimp but that should not be something complex.